Ultrasound-guided therapeutic injections for neural pathology about the foot and ankle: a 4 year retrospective review

Tips and tricks in ultrasound-guided musculoskeletal interventional procedures

Ultrasound visualization affords proceduralists versatile and accurate guidance for a variety of percutaneous, minimally invasive procedures in the musculoskeletal system including joint (intra-articular) injections or aspirations, intra-bursal injections, peritendinous, and perineural injections. A variety of percutaneous procedures are traditionally performed blindly, but may be more easily or more accurately performed with the real-time assistance of ultrasound guidance. Other procedures are only possible utilizing image-guidance, due to the required precision of the injection because of delicate local anatomy or depth of the injection; ultrasound is a safe, portable, and widespread modality that can be used to assist the proceduralist in localizing the needle tip in such cases, to ensure safe and accurate delivery of the medication, most frequently a solution of steroid and anesthetic. This review aims to provide a foundational approach to ultrasound-guided procedures in the musculoskeletal system, offering tips and tricks that can be employed in many different procedures including intra-articular, juxta-articular, and perineural injections for a multitude of clinical scenarios. Technical considerations regarding ultrasound transducer selection, sonographic technique, as well as common indications, contraindications, and complications of these procedures, are presented. Additionally, a variety of pharmacologic considerations for proceduralists contemplating ultrasound-guided injections are discussed.

Interventional Imaging Techniques as Alternative to Surgery of the Foot and Ankle

A variety of foot and ankle pathologies can impair patient's daily activities, ultimately requiring surgical management. However, with improvements in image-guided intervention, the joints, soft tissues, and osseous structures may be accessible using various percutaneous techniques as a potential alternative therapeutic tool, avoiding the need for surgery with its associated risks and morbidity. This article discusses the potential range of image-guided interventional treatments. Injections, aspiration, biopsies, cryoablation, and radiofrequency ablation are described. Newer novel treatments are also covered. Finally, the common pathologies of Morton's neuroma, Achilles tendinopathy, and plantar fasciitis are addressed.

US for Traumatic Nerve Injury, Entrapment Neuropathy, and Imaging-guided Perineural Injection

US is commonly performed to help diagnose traumatic peripheral nerve injury and entrapment neuropathy, particularly with superficial nerves, where higher spatial resolution provides an advantage over MRI. Other advantages of US include dynamic evaluation, easy contralateral comparison, fewer implant contraindications, less artifact from ferromagnetic debris, and facile needle guidance for perineural injections. The authors review peripheral nerve US for traumatic peripheral nerve injury with an emphasis on injury grading and entrapment neuropathy and describe best-practice techniques for US-guided perineural injections while highlighting specific techniques and indications. Online supplemental material is available for this article. ^©RSNA, 2022.

Clinical indications for image-guided interventional procedures in the musculoskeletal system: a Delphi-based consensus paper from the European Society of Musculoskeletal Radiology (ESSR)-part VII, nerves of the lower limb

OBJECTIVES

To perform a Delphi-based consensus on published evidence on image-guided interventional procedures for peripheral nerves of the lower limb (excluding Morton's neuroma) and provide clinical indications.

METHODS

We report the results of a Delphi-based consensus of 53 experts from the European Society of Musculoskeletal Radiology who reviewed the published literature for evidence on image-guided interventional procedures offered around peripheral nerves in the lower limb (excluding Morton's neuroma) to derive their clinical indications. Experts drafted a list of statements and graded them according to the Oxford Centre for evidence-based medicine levels of evidence. Consensus was considered strong when > 95% of experts agreed with the statement or broad when > 80% but < 95% agreed. The results of the Delphi-based consensus were used to write the paper.

RESULTS

Nine statements on image-guided interventional procedures for peripheral nerves of the lower limb have been drafted. All of them received strong consensus. Image-guided pudendal nerve block is safe, effective, and well tolerated with few complications. US-guided perisciatic injection of anesthetic provides good symptom relief in patients with piriformis syndrome; however, the addition of corticosteroids to local anesthetics still has an unclear role. US-guided lateral femoral cutaneous nerve block can be used to provide effective post-operative regional analgesia.

CONCLUSION

Despite the promising results reported by published papers on image-guided interventional procedures for peripheral nerves of the lower limb, there is still a lack of evidence on the efficacy of most procedures.

KEY POINTS

• Image-guided pudendal nerve block is safe, effective, and well tolerated with few complications. • US-guided perisciatic injection of anesthetic provides good symptom relief in patients with piriformis syndrome; however, the addition of corticosteroids to local anesthetics still has an unclear role. • US-guided lateral femoral cutaneous nerve block can be used to provide effective post-operative regional analgesia. The volume of local anesthetic affects the size of the blocked sensory area.

Clinical indications for image-guided interventional procedures in the musculoskeletal system: a Delphi-based consensus paper from the European Society of Musculoskeletal Radiology (ESSR)-part VI, foot and ankle

Objectives

Clarity regarding accuracy and effectiveness for interventional procedures around the foot and ankle is lacking. Consequently, a board of 53 members of the Ultrasound and Interventional Subcommittees of the European Society of Musculoskeletal Radiology (ESSR) reviewed the published literature to evaluate the evidence on image-guided musculoskeletal interventional procedures around this anatomical region.

Methods

We report the results of a Delphi-based consensus of 53 experts from the European Society of Musculoskeletal Radiology who reviewed the published literature for evidence on image-guided interventional procedures offered around foot and ankle in order to derive their clinical indications. Experts drafted a list of statements and graded them according to the Oxford Centre for evidence-based medicine levels of evidence. Consensus was considered strong when > 95% of experts agreed with the statement or broad when > 80% but < 95% agreed. The results of the Delphi-based consensus were used to write the paper that was shared with all panel members for final approval.

Results

A list of 16 evidence-based statements on clinical indications for image-guided musculoskeletal interventional procedures in the foot and ankle were drafted after a literature review. The highest level of evidence was reported for four statements, all receiving 100% agreement.

Conclusion

According to this consensus, image-guided interventions should not be considered a first-level approach for treating Achilles tendinopathy, while ultrasonography guidance is strongly recommended to improve the efficacy of interventional procedures for plantar fasciitis and Morton’s neuroma, particularly using platelet-rich plasma and corticosteroids, respectively.

Key Points

• The expert panel of the ESSR listed 16 evidence-based statements on clinical indications of image-guided musculoskeletal interventional procedures in the foot and ankle.

• Strong consensus was obtained for all statements.

• The highest level of evidence was reached by four statements concerning the effectiveness of US-guided injections of corticosteroid for Morton’s neuroma and PRP for plantar fasciitis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-021-08125-z.

Ultrasound-guided diagnostic deep peroneal nerve blocks prior to potential neurectomy: a retrospective review

OBJECTIVE

To describe our technical and preliminary clinical experience with ultrasound-guided diagnostic deep peroneal nerve (DPN) blocks for patients considering deep peroneal neurectomy.

MATERIALS AND METHODS

Retrospective analysis of ultrasound-guided diagnostic DPN blocks performed in the anterior lower leg in patients pursuing deep peroneal neurectomy for foot pain not directly attributable to the DPN. Patient age, sex, foot laterality, diagnosis, nerve block complications, location of the DPN with respect to vascular landmarks in the lower leg, pain relief from nerve block, and pain relief from neurectomy (if performed) were recorded.

RESULTS

Twenty-six DPN blocks were performed for 25 feet, of which a majority had pain attributable to midfoot osteoarthritis (22/25). Variable DPN locations with respect to vascular landmarks in the lower leg were observed, including lateral to the anterior tibial artery (12/25), anterior to the artery (5/25), medial to the artery (3/25), lateral to the lateral paired vein (4/25), and 1-cm lateral to the artery (1/25). After DPN blocks, patients reported pain relief in 22/25 feet. Of the eleven patients who proceeded to have a deep peroneal neurectomy, ten reported improved foot pain.

CONCLUSION

Diagnostic deep peroneal nerve blocks for patients considering deep peroneal neurectomy for denervation therapy should be performed in the anterior lower leg where the anterior tibial vessels serve as anatomic landmarks. Those who perform DPN blocks with ultrasound guidance should be aware of variable DPN position with respect to the vascular landmarks.

Ultrasound-guided Therapeutic Injection and Cryoablation of the Medial Plantar Proper Digital Nerve (Joplin's Nerve): Sonographic Findings, Technique, and Clinical Outcomes

RATIONALE AND OBJECTIVES

The medial plantar proper digital nerve, also called Joplin's nerve, arises from the medial plantar nerve, courses along the medial hallux metatarsophalangeal joint, and can be a source of neuropathic pain due to various etiologies, following acute injury including bunion surgery and repetitive microtrauma. We describe our clinical experience with diagnostic ultrasound assessment of Joplin's neuropathy and technique for ultrasound-guided therapeutic intervention including both injection and cryoablation over a 6-year period.

MATERIALS AND METHODS

Retrospective review of all diagnostic studies performed for Joplin's neuropathy and therapeutic Joplin's nerve ultrasound-guided injections and cryoablations between 2012 and 2018 was performed. Indications for therapeutic injection and cryoablation, were recorded. Studies were assessed for sonographic abnormalities related to the nerve and perineural soft tissues. Post-treatment outcomes including immediate pain scores, clinical follow-up, and periprocedural complications were documented.

RESULTS

Twenty-four ultrasound-guided procedures were performed, including 15 perineural injections and nine cryoablations. With respect to sonographic abnormalities, nerve thickening (33%) and perineural hypoechoic scar tissue (27%) were the most common findings. The mean pain severity score prior to the therapeutic injection was 6.4/10 (range 4-10) and 0.25/10 (range 0-2) following the procedure; mean follow-up was 26.2 months (range 3-63 months). All of the cryoablation patients experienced sustained pain relief with a mean length follow-up of 3.75 months (range 0.2-10 months).

CONCLUSION

Therapeutic injection of Joplin's nerve is a safe and easily performed procedure under ultrasound guidance, with high rates of immediate symptom improvement. For those experiencing a relapse or recurrent symptoms, cryoablation offers an effective secondary potential treatment option.

Targeted Ultrasound-Guided Perineural Hydrodissection of the Sciatic Nerve for the Treatment of Piriformis Syndrome

Piriformis syndrome is a common cause of lumbar, gluteal, and thigh pain, frequently associated with sciatic nerve symptoms. Potential etiologies include muscle injury or chronic muscle stretching associated with gait disturbances. There is a common pathological end pathway involving hypertrophy, spasm, contracture, inflammation, and scarring of the piriformis muscle, leading to impingement of the sciatic nerve. Ultrasound-guided piriformis injections are frequently used in the treatment of these pain syndromes, with most of the published literature describing injection of the muscle. We describe a safe, effective ultrasound-guided injection technique for the treatment of piriformis syndrome using targeted sciatic perineural hydrodissection followed by therapeutic corticosteroid injection.

Ultrasound Imaging of Disorders of Small Nerves of the Extremities: Less Recognized Locations

Ultrasound is a well-proven imaging modality for showing peripheral nerve disorders and guiding perineural injections. The aim of this review is to focus on small peripheral nerve abnormalities, which are usually not recognized by sonologists. In fact, most of these small nerves have a tiny diameter (<2 mm), and their anatomy is less familiar. We describe the most common causes of small peripheral nerve disorders, providing an accurate description of their anatomic locations and relationships with adjacent structures; we also focus on technical hints that may help in their evaluation.

Sonographic evaluation of uncommonly assessed upper extremity peripheral nerves: anatomy, technique, and clinical syndromes

Targeted ultrasound of the median, ulnar, and radial nerves is a well-established technique for suspected upper extremity peripheral neuropathy. However, sonographic imaging of the brachial plexus and smaller peripheral nerve branches is more technically difficult and the anatomy is less familiar to many radiologists. As imaging techniques improve, many clinicians refer patients for imaging of previously less-familiar structures. In addition, some patients may present with injuries that could involve local neurovascular structures. Finally, patients presenting with isolated peripheral neuropathies may be referred for perineural injections with local anesthetic for diagnostic purposes, or steroid for therapeutic reasons. This requires sonologists to have a firm understanding of the courses of these nerves and the surrounding anatomic landmarks that can be used to accurately identify and characterize them. We discuss clinical syndromes referable to specific peripheral nerve branches in the upper extremity, the relevant anatomy, and sonographic technique.

Society of Skeletal Radiology 2017 annual meeting summary

Peer-reviewed abstracts presented at the 2017 Society of Skeletal Radiology (SSR) Annual Meeting were reviewed following oral presentation. Topics felt to be of potential interest to musculoskeletal (MSK) investigators and practicing clinicians are highlighted in this compilation and analysis of the meeting. New concepts regarding MSK imaging and intervention, MSK protocols and techniques and quality improvement are included. ePoster highlights are also presented.